Using Audi Quatro Transaxle (8HP55) with a V12 - Adaptors

The 8HP55 is an 8 speed automatic transaxle used in Audi Quatro vehicles. Its rated at 550 Nm and as its 8 speed, has very low 1st and 2nd, close ratio 3rd to 6 and overdrive 7 and 8th. Shift points can be programmed to match torque curves of the engine using a Turbo Lamic TCU. There is even provision to add a clutch pedal to this box to convert it to fully manual. This looks like an amazing candidate for a transaxle.

Im currently designing an adaptor to go with this transaxle and Im trying to mate it to a Jag V12 6.0 engine. As the front diff is mounted within the engine plane it requires a funky cutout for the diff and a depth of around 78mm to space it so it will fit.

Im getting the transaxle measured by a third party and have measured my V12 using calipers. Im down to around 15 thou error (I think!) and I dont suppose anyone has the V12 6.0 bellhousing dimensions that I could use to crosscheck?

Adaptor.png
 

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I'm not sure it will work for a GT40. Depends on its length. As the differential output flanges are close to the bell housing face it's also going to need a fairly wide rear suspension frame. This will likely preclude its use in original style vehicles.
 
The output shaft just needs to be removed and a blanking plate installed. The front diff on the trans will be driving the rear wheels. This is going into a mid engined car (not rear engined).
 
The transmission guy will be removing and configuring the transaxle, he has assessed and said its doable. For torque rating, yes, the front diff will take the full load. The 8HP55 is rated at 510 Nm or 410 lb/ft. So yes the diff section is underated for the V12. Worst case I will get it rebuilt with HD parts.
 
If you take out the center diff, then you will go nowhere, as the diff is required to distribute torque to the front and rear axles. The front diff is also only designed to handle about 30-40% of the torque of the engine, as the remainder of torque is sent to the rear wheels.
 
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